Take a moment to remember the Sony's PDD (Professional Disc for Data) format, which is, after all, the precursor to (and a "pro" version of) today's Blu-ray disc, which is now taking its place as the golden child of Sony's media roadmap. If you've already made a sizable investment in PDD, you're not clean out of luck, however. Sony will keep selling PDD drives through the end of next year, and will provide tech support and keep media available until at least 2014. But don't hope for a next-gen PDD format that can hold more than today's 23GB discs.